要怎麼Image1截屬JPEG格式到Image2

我參考了 BMP方法
[code cpp]
Graphics::TBitmap *Bmp = new Graphics::TBitmap();
Byte *ptr;
int r,g,b;
int gray;
int i,j;
int threshold;
Bmp->Assign(Image1->Picture->Bitmap);
Bmp->PixelFormat=pf24bit;

Image2->Picture->Assign(Bmp);
delete Bmp ;
[/code]

但是我使用了TJPEGImage 但是IMAGE2也沒出現圖片 ~
而且讀取的IMAGE1圖片也是JPEG為什麼IMAGE2沒有圖片
[code cpp]
TJPEGImage *jpeg = new TJPEGImage;
jpeg->Assign(Image1->Picture->Bitmap);
jpeg->PixelFormat = jf24Bit;
Image2->Picture->Assign(jpeg);
delete jpeg ;
[/code]

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May I ask you something ?

編輯記錄

Image1->Picture->LoadFromFile如果是jpeg檔，圖應該要找Image1->Picture->Graphic，不是Image1->Picture->Bitmap
bmp檔則是Graphic和Bitmap都可
[code cpp]
TJPEGImage *jpeg = new TJPEGImage;
jpeg->Assign(Image1->Picture); //或Image1->Picture-Graphic
jpeg->PixelFormat = jf24Bit;
Image2->Picture->Assign(jpeg);
delete jpeg;
[/code]

補充一下
[code cpp]
Image2->Picture->Assign(jpeg); //Image2->Picture->Graphic->ClassName()會是TJPEGImage，沒有Image2->Picture->Bitmap
//若改
Image2->Picture->Bitmap->Assign(jpeg); //Image2->Picture->Graphic->ClassName()會是TBitmap，有Image2->Picture->Bitmap
[/code]

編輯記錄